Pipe crimping apparatus

ABSTRACT

A pipe crimping apparatus comprises a holding device to externally engage and hold a joint to be crimped. The holding device has a concavity in which a part cylindrical plate member is secured, the concavity and plate member defining a part cylindrical clamping zone. One pair of crimping arms is pivotally mounted on the holding device. Each arm is movable relative to the clamping zone. Handles are provided to cause movement of the arms relative to the clamping zone wherein the arms, in a crimping movement, extend radially into the clamping zone to engage a joint, and impress by indentation portions of an outer socket end onto an inner spigot end to secure the same together.

CROSS-REFERENCE TO RELATED APPLICATIONS

This is a 35 USC 371 application of PCT/GB 99/01649 filed on Jun. 7,1999.

This invention relates to a pipe crimping apparatus for crimping thejoints of pipe connections of the type having non-flux, non-solderjoints, for example, those described in my UK Patent No. GB 2 219 644.The purpose of crimping is to secure one length of pipe to anotherlength of pipe or to a pipe connector by impressing portions of theouter socket end onto the inner spigot end of the connection.

Accordingly, the present invention is a pipe crimping apparatuscomprising holding means to externally engage and hold a joint to becrimped, the holding means having a concavity defining a partcylindrical clamping zone, at least one pair of crimping arms pivotallymounted on the holding means, each arm being movable relative to theclamping zone and means to cause movement of the arms relative to theclamping zone wherein the arms, in a crimping movement, extend radiallyinto the clamping zone to engage a joint, and impress by indentationportions of an outer socket end onto an inner spigot end to secure thesame together wherein the holding means is an elongate block with theconcavity in one peripheral side with both ends of the block rebated toprovide two cheeks between which a respective crimping arm is pivoted,the crimping arms being similarly cranked and mounted in mirror-image onthe block with each arm provided at its crank to the respective cheeksof the block and the distal en of the outer part of each arm having aprotuberance directed inwardly towards the clamping zone.

Preferably, a part cylindrical plate member is secured in the concavitywith its axis normal to the longitudinal axis of the block, the clampingzone being provided in the plate member. Movement apart of the innerends of the inner parts of the arms causes inward movement of the distalends of the outer part of the arms. The plate member has desirablyopposed cut-outs extending inwards from its respective sides to allowfor movement of the arms therethrough.

Preferably also, the means to cause movement is a pair of handles withone end of each handle pivoted to a respective inner end of one innerpart of an arm, the handles being pivoted together through a link nearto the one end with the other end of the handles serving as hand grips.Movement of the hand grips together causes movement apart of the innerends of the arms and consequential inward crimping movement of thedistal ends of the arms.

Preferably further, the block has a spindle extending normally from theother longitudinal side to pass through a bore in the link, the spindlemoving freely through the bore on closing and opening of the hand grips.

BRIEF DESCRIPTION OF THE DRAWINGS

An embodiment of the present invention will now be described, by way ofexample, with reference to the accompanying drawings, in which:

FIG. 1 is a perspective view of a pipe crimping apparatus according tothe present invention and showing a first connection between a pair ofcrimping arms and a pair of handles;

FIG. 2 is a front view of the apparatus;

FIG. 3 is a side view of the apparatus;

FIG. 4 is an underneath plan view of the apparatus;

FIG. 5A is a front view of the apparatus showing a second form ofconnection between the handles and the arms;

FIG. 5B is a front view of the apparatus showing a third indentationmeans, and

FIGS. 6A and 6B are respectively two modifications of the apparatusshowing different means to cause movement.

Referring to the drawings, a pipe crimping apparatus comprises holdingmeans 10 to externally engage and hold a joint (not shown) to becrimped. The holding means 10 is an elongate block 12 with a concavityin one peripheral side thereof. A part cylindrical plate member 14 issecured in the concavity with its axis normal to the longitudinal axisof the block 12. The concavity and plate member 14 define a partcylindrical clamping zone. On the inside of the plate member 14, twogripping members 32 are provided spaced apart a determined distance toprovide with the face of the plate member 14 a complementary shape tothe outer shape of the joint.

One pair of crimping arms 16 are pivotally mounted on the block 12, eacharm 16 being movable relative to the clamping zone.

Both ends of the block 12 are rebated to provide two cheeks 18 betweenwhich a respective crimping arm 16 is pivoted on pin 15. The crimpingarms 16 are similarly cranked and mounted in mirror-image on the block12 with each arm 16 pivoted at its crank to the respective cheeks 18 ofthe block 12. The distal end of the outer part 16A of each arm 16 has aprotuberance 20, formed by a ball-bearing set into a recess, directedinwardly towards the clamping zone provided in the plate member 14.Movement apart of the inner ends of the inner parts 16B of the arms 16causes inward movement of the distal ends of the outer part 16A of thearms 16. The plate member 14 has opposed cut-outs extending inwards fromits respective sides to allow for movement of the outer parts 16A of thearms 16 therethrough.

Means (as shown in FIGS. 1 to 4) is provided to cause movement of thearms 16 relative to the clamping zone wherein the arms 16, in a crimpingmovement, extend radially into the clamping zone to engage a joint, andthe protuberances impress by indentation portions of an outer socket endonto an inner spigot end to secure the same together. The means is apair of handles 22 with one end of each handle 22 pivoted to arespective inner end of one inner part 16B of an arm 16, the handles 22being pivoted together through a link 24 near to the one end with theother end of the handles 22 serving as hand grips. Movement of the handgrips together causes movement apart of the inner ends of the arms 16and consequential radial inward crimping movement of the distal ends ofthe arms 16. A spring 28 is provided between the two handles 22 as shownto urge the hand grips apart, and a stop 30 is provided on one handle 22at the hand grip portion to space the handles 22 apart and to preventthe indentations being too deep.

In an alternative form of connection between the handles 22 and the arms16 and to allow the handles to be at an angular disposition to the block12 and arms 16, the inner ends 16B of the arms 16 are each connected bya spring 34 to a common anchorage 36 on the block 12. The one end of thehandles 22 are connected to the inner ends 16B of the arms 16 by pivotpins 38 (represented by a dotted line) whose axes are at ninety degreesto the other pivot pins and to form knuckle joints whereby the handles22 can be rotated through up to ninety degrees from the block 12 and bestill able to operate the crimping arms 16.

The block 12 has a spindle 26 extending normally from the otherlongitudinal side to pass through a bore in the link 24, the spindle 26moving freely through the bore on closing and opening of the hand grips.

Alternatively to the spindle 26, a third indentation means is providedin which a bolt 40 is provided in screw-threaded engagement with link 24the bolt 40 having a rounded inner end to extend through the block 12and plate 14 as shown and provide a third protuberance 20, the spaceddisposition of the three protuberances 20 being at substantially 60° toeach other. A stop 44 is provided by a nut being in screw-threadedengagement on the bolt 40, the stop 44 abutting against the block 12 andbeing movable to adjust the depth of the protuberance 20. The link 24 inthis case is in three hinged parts 24A, 24B and 24C. A coil spring 46surrounds the bolt 40 and abuts against block 12 and link part 24B. Theinner ends of the arms 16 are provided with a slot 48 instead of a pivothole whereby the pivots of the handles 22 can move theredown during asecond stage of use. The spring 46 has a tension which is only overcomewhen the arms 16 have been moved during a first stage to cause the firsttwo indentations, the bolt 40 then in the second stage moves down toform a third indentation.

In a modificaiton (not shown) of the third indentation means, the stop44 can be provided above the link part 24B to abut against the topthereof, the bolt being correspondingly altered to provide for such anarrangement.

In FIGS. 6A and 6B, alternative movement means are shown. FIG. 6A showsthe movement means in the form of a hydraulic or pneumatic cylinder andram arrangement 50 in which the arrangement 50 replaces the link 24 andis connected between the slots 48 of the inner parts 16B of the arms 16.A third indentation means is provided as shown. FIG. 6B shows themovement means in the form of a Bowden cable arrangement with two smallhandles 52 and a link 24. The Bowden cable arrangement is positionedbetween the outer ends of the handles 52 and a coil spring 54 isprovided between the handles 52 around cable 56. A stop 58 is providedon the cable 56 between the handles 52. A third indentation means can beprovided but is not shown. The operation of both arrangements moving thearms 16 in a similar manner to that described above in the embodiment.

In a first modification, the protuberance 20 is provided by a roundedouter end of a grub screw (not shown) in threaded engagement with atapped bore in the distal end of the outer part 16A of each arm 16. Thismodification allows for adjustment in the depth of the protuberance.

In a second modification, an adjustable stop (not shown) is provided inthe outer part 16A of each arm 16 inboard of the protuberance 20, thestops being to abut against respective parts of the block 12 to ensurethe depth of the indentations is substantially equal.

Variations and modifications can be made without departing from thescope of the invention described above and as claimed hereinafter.

The foregoing relates to preferred exemplary embodiments of theinvention, it being understood that other variants and embodimentsthereof are possible within the spirit and scope of the invention, thelatter being defined by the appended claims.

What is claimed is:
 1. A pipe crimping apparatus comprising holdingmeans to externally engage and hold a joint to be crimped, the holdingmeans having a concavity defining a part cylindrical clamping zone, atleast one pair of crimping arms pivotally mounted on the holding means,each arm being movable relative to the clamping zone and means to causemovement of the arms relative to the clamping zone wherein the arms, ina crimping movement, extend radially into the clamping zone to engage ajoint, and impress by indentation portions of an outer socket end ontoan inner spigot end to secure same together wherein the holding means isan elongate block with the concavity in one peripheral side with bothends of the block being rebated to provide two cheeks between which arespective crimping arm is pivoted, the crimping arms being similarlycranked and mounted in mirror-image on the block with each said armpivoted at its crank to the respective cheeks of the block and a distalend of an outer part of each said arm has a protuberance directedinwardly towards the clamping zone.
 2. An apparatus according to claim1, wherein a part cylindrical plate member is secured in the concavitywith its axis normal to a longitudinal axis of the block, the clampingzone being provided in the plate member.
 3. An apparatus according toclaim 2, wherein the plate member has opposed cut-outs extending inwardsfrom its respective sides to allow for movement of the armstherethrough.
 4. An apparatus according to claim 3, wherein the movementmeans is a cylinder and ram arrangement connected between the innerparts of the arms.
 5. An apparatus according to claim 3, wherein themovement means is in form of a bowden cable arrangement connectedbetween two small handles pivoted to the inner parts of the arms.
 6. Anapparatus according to claim 2, wherein two gripping members areprovided on the plate member spaced apart a determined distance toprovide with a face of the plate member a complementary shape to theouter shape of a joint to be crimped.
 7. An apparatus according to claim1, wherein each of the arms have an inner part with an inner end andmovement apart of the inner ends of the inner parts causes inwardmovement of the distal ends of the outer part of the arms.
 8. Anapparatus according to claim 7, wherein the plate member has opposedcut-outs extending inwards from its respective sides to allow formovement of the arms therethrough.
 9. An apparatus according to claim 7,wherein the movement means is a cylinder and ram arrangement connectedbetween the inner parts of the arms.
 10. An apparatus according to claim9, wherein a third indentation means is provided acting into theclamping zone from between the inner parts of the arms, a protuberanceof said third indentation means and the other two protuberances beingsubstantially equi-spaced apart.
 11. An apparatus according to claim 7,wherein the movement means is in form of a bowden cable arrangementconnected between two small handles pivoted to the inner parts of thearms.
 12. An apparatus according to claim 11, wherein a thirdindentation means is provided acting into the clamping zone from betweenthe inner parts of the arms, a protuberance of said third indentationmeans and the other two protuberances being substantially equi-spacedapart.
 13. An apparatus according to claim 7, wherein a thirdindentation means is provided acting into the clamping zone from betweenthe inner parts of the arms, a protuberance of said third indentationmeans and the other two protuberances being substantially equi-spacedapart.
 14. An apparatus as claimed in claim 7, wherein two grippingmembers are provided on the plate member spaced apart a determineddistance to provide with a face of the plate member a complementaryshape to the outer shape of a joint to be crimped.
 15. An apparatusaccording to claim 1, wherein the means to cause movement is a pair ofhandles with one end of each handle pivoted to a respective inner end ofone inner part of an arm, the handles being pivoted together through alink near to the one end with an other end of each handle serving as ahand grip.
 16. An apparatus according to claim 15, wherein movement ofthe hand grips together causes movement apart of the inner ends of thearms and consequential inward crimping movement of the distal ends ofthe arms.
 17. An apparatus according to claim 16, wherein the block hasa spindle extending normally from one longitudinal side to pass througha bore in the link, the spindle moving freely through the bore onclosing and opening of the hand grips.
 18. An apparatus according toclaim 15, wherein the block has a spindle extending normally from onelongitudinal side to pass through a bore in the link, the spindle movingfreely through the bore on closing and opening of the hand grips.
 19. Anapparatus according to claim 16, wherein each said handle is connectedto a respective crimping arm through a knuckle joint.
 20. An apparatusas claimed in claim 1, wherein the movement means is in the form of abowden cable arrangement connected between two small handles pivoted tothe inner parts of the arms.
 21. An apparatus as claimed in claim 1,wherein a third indentation means is provided acting into the clampingzone from between the inner parts of the arms, a protuberance of saidthird indentation means and the other two protuberances beingsubstantially equi-spaced apart.